There are many applications for providing fluids separately and in a blended condition. For example, in connection with service stations for dispensing motor fuel products, two or more fuel products with different octane ratings are dispensed separately, and a blending system is often provided for blending the products. A conventional system of this type utilizes two meters of identical, relatively high, volumetric accuracy so that when either product flows, the required accuracy is available for each product. In these arrangements, when a blended fuel is dispensed, the readings of the two meters are added together to obtain the total volume. The ratio between the two products is obtained and controlled using the two meters, but the volumetric accuracy of each individual meter exceeds the volumetric accuracy requirements of the blended fuel and is costly.
Another problem with prior art arrangements of this type is that the master meter often has a relatively high volumetric capacity. Therefore, when the product to be dispensed is changed, the product that was previously dispensed accumulates in the meter and mixes with the next product to be dispensed. This could cause the quality of the latter product to fall outside regulatory, or other, requirements.
Therefore, what is need is a blending system for two or more fluids which eliminates the need for a relatively costly meter for each fluid. Also needed is a system and method of the above type in which the master meter has a relative low volumetric capacity to avoid the accumulation of any previously dispensed fuel in the meter.